The present invention is directed to a connector and a method of manufacturing the same, and more specifically, to a connector having an insulating housing and an insertable EMI (Electromagnetic Interference) filter through which selected signal transmission members of a plurality of signal transmission members extend.
Heretofore, in a connector that has an insulating housing and multiple signal transmission members that are inserted therethrough and whose conductors are electrically connected to each other, connectors have been used in which electromagnetic interference (EMI) measures are taken by causing signal transmission members to pierce a ferrite core, as shown, for example, with the connector described in unexamined utility model H1-140786 [1989]. In such prior art connectors, it is normally very difficult to form the housing and ferrite core by integral molding, so they are each manufactured separately, and during assembly the ferrite core is forcibly inserted into and mounted inside the housing, which makes manufacturing the connector more complicated.
In another prior art connector, the housing itself is formed by a ferrite core, and multiple connector pins that act as signal transmission members are inserted inside (as described in examined patent H7-48427 [1995]). With such a prior art connector, there is no need to separately provide ferrite pieces or other filter elements, and a connector having EMI measures can be made by a simple manufacturing process. Also, such a connector is suitable for power source lines in that adequate EMI measures can be applied. However, in such a structure the ferrite core acts as an impedance element provided on each connector pin. Therefore if such a connector is used as a connector for a DC power source that consists of voltage impression wires and grounding wires, the problem arises that a ferrite core will also be provided on the grounding wire part, for which no EMI measures actually need to be taken, and because this ferrite core will act as an impedance element, a standard electric potential will arise between conductors connected by the grounding wires, and it becomes difficult to make uniform the standard electric potentials of all the conductors connected by the grounding wires.
It is an object of the present invention, therefore, to provide a connector in which an EMI filter is arranged according to the electrical signals that flow along the signal lines.
It is a further object of the present invention to provide a connector in which selected signal transmission members extend through an EMI filter and selected signal transmission members do not.
It is a still further object of the present invention to provide a connector that can be manufactured with a drop-insertable EMI filter.
Still other objects and advantages of the invention will become clear upon review of the following detailed description in conjunction with the appended drawings.
A connector is provided with an insulating housing and multiple signal transmission members that are inserted through said housing. The signal transmission members are arranged parallel to a direction that is perpendicular to the direction in which they are inserted through said insulating housing, and formed in said insulating housing is a core insertion part into which is inserted an EMI filter or a ferrite core that is pierced by at least some of the signal transmission members among said multiple transmission members. Thus, the signal transmission members that pierce the ferrite core may be signal lines along which electrical signals flow, and the signal transmission members that do not pierce the ferrite core may be grounding wires or the like. Thus, it is possible to prevent the ferrite core from also acting as an impedance element on the grounding wires.
A method of manufacturing the connector is also provided, where the EMI filter or ferrite core may be simply inserted or dropped into the core insertion part of the insulating housing, which is easier to manufacture than if the ferrite core needed to be forcibly inserted. It is desirable that the cross-section of the core insertion part be concave, so that the EMI filter or ferrite core can be easily seated within such insertion part. Also, by inserting a plurality of signal transmission members through the insulating housing and by causing select transmission lines to pierce the ferrite core after the ferrite core has been inserted into the core insertion part, it becomes possible to securely fix said ferrite core in its prescribed position, without the ferrite core becoming dislodged from the core insertion part.